The present invention relates to vacuum cleaners. More particularly, the present invention relates to upright vacuum cleaners used for suctioning dirt and debris from carpets and floors.
Upright vacuum cleaners are ubiquitous. They are known to include an upper portion having a handle, by which an operator of the vacuum cleaner may grasp and maneuver the cleaner, and a lower cleaning nozzle portion which travels across a floor, carpet, or other surface being cleaned. The upper portion is often formed as a rigid plastic housing which encloses a dirt and dust collecting filter bag, although the upper portion may simply be an elongated handle with the filter bag, and an external cloth bag, being connected thereto. The cleaning nozzle is hingedly connected to the upper portion such that the upper portion is pivotable between a generally vertical upright storage position and an inclined operative position. The underside of the nozzle includes a suction opening formed therein which is in fluid communication with the filter bag.
A vacuum or suction source such as a motor and fan assembly is enclosed either within the nozzle portion or the upper portion of the cleaner. The vacuum source generates the suction required to pull dirt from the carpet or floor being vacuumed through the suction opening and into the filter bag. A rotating brush assembly is typically provided in proximity to the suction opening to loosen dirt and debris from the carpet being vacuumed.
While upright vacuum cleaners are generally very effective and are in widespread use, there has been found a need to provide a more effective and easy to use upright vacuum cleaner. Specifically, although attempts have been made to provide an upright vacuum cleaner for suctioning dirt from the corners and edges of a room, these prior edge and corner cleaning upright vacuum cleaners have not been entirely effective or easy to use. The lack of complete effectiveness generally results from the inability to extend the suction opening of the vacuum cleaner nozzle completely to or beyond the edges of the nozzle housing. Furthermore, when attempting to clean edges and corners of a room with known upright vacuum cleaners, the housing of the nozzle interferes with the walls and prevents the suction opening of the nozzle from being moved close to the wall as is required for effective corner and edge cleaning.
Prior edge cleaning vacuums have also been relatively complex and expensive to manufacture. The edge cleaning mechanisms have been permanently incorporated into the cleaning nozzle of the vacuum, and have required the operator of the vacuum to operate a lever, knob, or the like to divert a portion of the suctioning force away from the main suction opening in the underside of the nozzle to the edge/corner cleaning assembly.
One deficiency associated with known edge cleaning mechanisms is the inability of these mechanisms to divert a sufficient amount of the available suction to the edge cleaning assembly. Instead, during edge and corner cleaning operations, the suction is present at both the main suction opening and the edge cleaning suction opening, resulting in less powerful suction at both locations. This results in an ineffective suctioning of dirt and debris from the edges and corners.
Another deficiency of known upright vacuum cleaners, both with and without edge cleaning capabilities, is the difficulty encountered in maneuvering these cleaners over carpets and floors. Most upright vacuum cleaners include four wheels extending from the underside of the nozzle, with one wheel located at or near each corner of the nozzle. Each wheel rotates about a horizontal axis but is otherwise fixed in position, i.e., the wheels do not pivot about a vertical or near vertical axis. While some prior vacuum cleaners have utilized casters to facilitate maneuverability, these prior vacuums have either used all casters, which can make control of an upright vacuum cleaner difficult in light of the repetitive back and forth vacuuming motion utilized, or have combined casters with narrow profile fixed wheels formed with a sharp transition (often close to 90 degrees) between the rolling surface and the side or hub portion thereof. These sharply transitioned wheels have been found to limit the maneuverability of a vacuum cleaner, especially if they were to be used in conjunction with casters. The sharp transition area between the rolling surface and the side of each wheel becomes engaged with a subadjacent carpet upon any lateral sliding movement or twisting of the wheel and thus limits the ability of the forward wheels to twist or slide laterally across a surface being cleaned as is required upon pivoting the vacuum upon its casters. The sharply transitioned wheels have also been found to mar the finish on uncarpeted floors.
The maneuverability of an upright cleaner is especially important when the cleaner is to be utilized for edge and corner cleaning. It is more difficult to maneuver the nozzle of an upright cleaner into the area of a room adjacent to the walls for edge and corner cleaning operations. Prior upright vacuum cleaners with edge cleaning capabilities have not included wheels that allow the cleaner to be easily and effectively maneuvered into areas adjacent to edges and corners of the room being cleaned. Prior edge cleaning vacuums have generally not included casters or any other similar wheels that enhance maneuverability. They have included merely fixed wheels, rotatable about only a single, generally horizontal axis. Thus, maneuvering these prior edge cleaning vacuums into position as required for edge and corner cleaning has required the wheels to be slid laterally across the surface being vacuumed or has required the operator of the vacuum to lift the front and/or rear wheels from the surface being vacuumed in order to move the front or rear of the nozzle laterally to position the nozzle adjacent to an edge or corner of a room. Therefore, these prior upright cleaners with edge cleaning capabilities have not been easy to utilize and have consequently been less effective in cleaning the areas near walls and in corners.
Accordingly, it is desirable to develop a new and improved upright vacuum cleaner which would overcome the foregoing difficulties and others while providing better and more advantageous overall results.